Liquid management system

Abstract

A liquid management system for supplying or receiving liquid at a controlled pressure, comprising: a closed reservoir having an inlet for receiving liquid from a first remote location and an outlet for supplying liquid to a second remote location; and a pumped outlet disposed in the reservoir and arranged to remove liquid and gas contained within the reservoir, the pumped outlet being disposed such that the level of liquid in the reservoir can be maintained at a constant height.

The invention claimed is: 
     
       1. A liquid management system for supplying or receiving liquid at a controlled pressure, comprising:
 a closed single-chamber reservoir having an inlet for receiving liquid from a first remote location and an outlet for supplying liquid to a second remote location; and 
 a liquid and gas pump in communication with a pumped outlet disposed in the closed single-chamber reservoir at a height, the liquid and gas pump being arranged to remove the liquid and gas at the height of the pumped outlet thereby maintaining a single constant level of the liquid across the entire closed single-chamber reservoir at the height of the pumped outlet. 
 
     
     
       2. A system according to  claim 1 , wherein the pumped outlet includes a tube which extends into the reservoir. 
     
     
       3. A system according to  claim 2 , wherein the tube is substantially horizontal. 
     
     
       4. A system according to  claim 2 , wherein the tube is substantially vertical within the reservoir. 
     
     
       5. A system according to  claim 2 , wherein the tube has a tapered opening within the reservoir. 
     
     
       6. A system according to  claim 1 , wherein the pumped outlet is an opening in a side wall of the reservoir. 
     
     
       7. A system according to  claim 1 , further comprising a pump attached to the pumped outlet, the pump configured to control air pressure within the closed single-chamber reservoir. 
     
     
       8. A system according to  claim 1 , wherein the system further comprises an additional pump arranged to pump gas into or out of the closed single-chamber reservoir through an orifice in the closed single-chamber reservoir. 
     
     
       9. A system according to  claim 8 , further comprising an additional pump controller. 
     
     
       10. A system according to  claim 1 , further comprising an orifice connecting the reservoir to a gas at above, below, or at atmospheric pressure configured to bleed gas, in use, into or out of the reservoir. 
     
     
       11. A system according to  claim 10 , further comprising means for controlling the orifice such that the pressure within the reservoir is controlled. 
     
     
       12. A system according to  claim 1 , wherein the height of the pumped outlet is variable. 
     
     
       13. A liquid delivery system including a liquid management system according to  claim 1  and including a liquid delivery device supplied with liquid from the liquid management system. 
     
     
       14. A system according to  claim 13 , wherein the liquid delivery device is a printhead. 
     
     
       15. A system according to  claim 13 , wherein the liquid delivery device is a sprayhead. 
     
     
       16. A system according to  claim 13 , wherein the liquid delivery device is the first remote location. 
     
     
       17. A system printer according to  claim 13 , wherein the liquid delivery device is the second remote location. 
     
     
       18. A liquid delivery system including two liquid management systems according to  claim 1  wherein one system supplies liquid to a liquid delivery device and the other system receives liquid from the liquid delivery device, thereby controlling the pressure of the liquid supplied to the liquid delivery device and the pressure of the liquid removed from the liquid delivery device, such that the liquid flows through the liquid delivery device at a controlled rate and at a controlled pressure. 
     
     
       19. The liquid management system of  claim 1 , wherein the pumped outlet is disposed at a greater height than the height of the outlet. 
     
     
       20. A liquid management system for supplying or receiving liquid at a controlled pressure, comprising:
 a closed single-chamber reservoir comprising an inlet for receiving liquid from a first remote location and an outlet for supplying liquid to a second remote location, the closed single-chamber reservoir defining a volume for holding liquid in fluid communication with the outlet; and 
 a liquid and gas pump in communication with a pumped outlet disposed in the closed single-chamber reservoir at a first height, the liquid and gas pump being arranged to remove the liquid and gas at the first height of the pumped outlet, thereby maintaining a level of the liquid in the closed single-chamber reservoir at the first height of the pumped outlet, wherein the first height is greater than the height of the outlet and thus defines the depth, at the outlet, of the liquid in fluid communication with the outlet.